Acetogenesis to ethanologenesis: facilitating NADH oxidation via reductive acetate uptake.

(Homo)acetogens, including Clostridium spp., represent an enigma in metabolic flexibility and diversity. Eubacterium callanderi KIST612 is an acetogen that produces n-butyrate with carbon monoxide (CO) as the carbon and energy source; however, the production route is unknown.

Propagation of random excitations in the polar representation of strongly nonlinear four-wave systems of turbulence.

The present work is concerned with the uncertainty propagation of the wave turbulent system. In particular, we study the temporal development and long-term behavior of the probability with respect to the amplitude and phase of complex-valued waves constituting the generic four-wave system of turbulence. Our approach to approximating the target distribution function is via the three steps: (i) to grasp the physical process described by the true turbulence model as random process, (ii) to determine the stochastic differential equation whose solution exhibits statistically similar behavior with the underlying turbulent signal, and (iii) to solve the corresponding Kolmogorov forward equation.

Two-Electron-Induced Reorganization of Cobalt Coordination and Metal-Ligand Cooperative Redox Shifting Co(I) Reactivity toward CO Reduction.

Electrochemical reorganization of complex structures is directly related to catalytic reactivity; thus, the geometric changes of catalysts induced by electron transfer should be considered to scrutinize the reaction mechanism. Herein, we studied electron-induced reorganization patterns of six-coordinate Co complexes with neutral N-donor ligands. Upon two-electron transfer into a Co center enclosed within a bulky π-acceptor ligand, the catalytic site exhibited different reorganization patterns depending on the ligand characteristics.

Quasi-Markovian property of strong wave turbulence.

This paper is concerned with the reduced-order modeling of the strongly nonlinear wave turbulence system. The motivation for such an attempt comes from the utility of the probabilistic coarse-grained model in facilitating the theoretical and numerical analysis of the true dynamical system model. One typical practice of simplifying the complex physical model is, in the spirit of Brownian motion, to replace the nonlinear interactions by white noise forcing and linear dissipation.

Solid-phase colorimetric sensor for hypochlorite.

By taking advantage of the powerful oxidation property of hypochlorite (OCl), we developed a solid-phase colorimetric sensor for the detection of OCl based on 13 nm AuNPs immobilized on a 3-aminopropyltriethoxysilane APTES-coated substrate. This colorimetric sensor utilizes the aggregation and anti-aggregation properties of AuNPs arising from the interaction between dithiothreitol (DTT) and OCl. When the amount of OCl increases, the color of the substrate changes from blue to red, allowing for naked-eye detection at concentrations as low as 2.

Solid-state colorimetric polydiacetylene liposome biosensor sensitized by gold nanoparticles.

Polydiacetylene (PDA), a conjugated polymer, has attracted attention for realization of a label-free real-time colorimetric biosensor because it exhibits large and rapid colorimetric responses upon the binding of biomolecules. This is due to the conformational distortion of its conjugated backbone. However, solid-state PDA biosensors for point-of-care diagnosis remain unexplored.

Generalized Langevin equation and the linear regression model with memory.

Because the existence of cheap emulators can give rise to potentially drastic computational savings as compared to direct numerical simulations of complex turbulence models, the study of reduced models has good practical relevance, and the guidelines regarding their construction from the true dynamical system model are much in demand. In accordance with this contemporary trend in science and engineering, we provide a new approach for the rigorous derivation of the linear reduced model with memory from the one-dimensional Majda-McLaughlin-Tabak (MMT) prototypical wave turbulence in thermal equilibrium. The basic idea in obtaining the physics-constrained autoregressive model is to perform the discretization in time of the generalized Langevin equation (GLE) governing a single wave profile of the true dynamical system model; the GLE formalized in the Mori-Zwanzig (MZ) projection theory is the exact reduced-order equation and the closed-form rearrangement of the canonical equation of motion for the Hamiltonian system.

Cascade model of wave turbulence.

We propose a cascade model of wave turbulence designed to simplify the study of this phenomenon in the way that shell models simplify the study of Navier-Stokes turbulence. The model consists of resonant quartets, in which some modes are driven and damped and others are shared by pairs of quartets and transferring energy between them, mimicking the natural energy transfer mechanism in weakly turbulent waves. A set of detailed-balance conditions singles out the case of the cascade model in equilibrium, for which we can explicitly derive a Gaussian equilibrium measure and a maximum-entropy principle using a Kolmogorov forward equation.

Development of a job rotation scheduling algorithm for minimizing accumulated work load per body parts.

Background: For the successful implementation of job rotation, jobs should be scheduled systematically so that physical workload is evenly distributed with the use of various body parts. However, while the potential benefits are widely recognized by research and industry, there is still a need for a more effective and efficient algorithm that considers multiple work-related factors in job rotation scheduling.

Objective: This study suggests a type of job rotation algorithm that aims to minimize musculoskeletal disorders with the approach of decreasing the overall workload.

Supplementation of dietary germanium biotite enhances induction of the immune responses by foot-and-mouth disease vaccine in cattle.

Background: After the recent outbreak of foot-and-mouth disease (FMD) in Korea, a vaccination policy has been applied to control the disease. In addition, several non-specific immune stimulators have been used without any scientific evidence that they would enhance the immune response after FMD vaccination and/or protect against FMD. Based on the current situation, the aim of this study was to evaluate the effect of the non-specific immune stimulator germanium biotite on FMD vaccination and immune responses in cattle.

Induction of immune responses in mice and pigs by oral administration of classical swine fever virus E2 protein expressed in rice calli.

Classical swine fever (CSF), caused by the CSF virus (CSFV), is a highly contagious disease in pigs. In Korea, vaccination using a live-attenuated strain (LOM strain) has been used to control the disease. However, parenteral vaccination using a live-attenuated strain still faces a number of problems related to storage, cost, injection stress, and differentiation of CSFV infected and vaccinated pigs.

Oral immunization of mice with Saccharomyces cerevisiae expressing a neutralizing epitope of ApxIIA exotoxin from Actinobacillus pleuropneumoniae induces systemic and mucosal immune responses.

An oral delivery system based on ApxIIA#5-expressed on Saccharomyces cerevisiae was studied for its potential to induce immune responses in mice. Murine bone marrow-derived dendritic cells (DCs) stimulated in vitro with ApxIIA#5-expressed on S. cerevisiae upregulated the expression of maturation and activation markers, leading to production of tumor necrosis factor-α, interleukin (IL)-1β, IL-12p70 and IL-10.

Generation of dispersion in nondispersive nonlinear waves in thermal equilibrium.

In this work, we examine the important theoretical question of whether dispersion relations can arise from purely nonlinear interactions among waves that possess no linear dispersive characteristics. Using two prototypical examples of nondispersive waves, we demonstrate how nonlinear interactions can indeed give rise to effective dispersive-wave-like characteristics in thermal equilibrium. Physically, these example systems correspond to the strong nonlinear coupling limit in the theory of wave turbulence.

Induction of protective immune responses against challenge of Actinobacillus pleuropneumoniae by oral administration with Saccharomyces cerevisiae expressing Apx toxins in pigs.

Actinobacillus pleuropneumoniae is a causative agent of porcine pleuropneumonia, a highly contagious endemic disease of pigs worldwide, inducing significant economic losses worldwide. Apx toxins, which are correlated with the virulence of A. pleuropneumoniae, were expressed in Saccharomyces cerevisiae and its possible use as an oral vaccine has been confirmed in our previous studies using a murine model.

Efficacy of thiolated eudragit microspheres as an oral vaccine delivery system to induce mucosal immunity against enterotoxigenic Escherichia coli in mice.

A vaccine delivery system based on thiolated eudragit microsphere (TEMS) was studied in vivo for its ability to elicit mucosal immunity against enterotoxigenic Escherichia coli (ETEC). Groups of mice were orally immunized with F4 or F18 fimbriae of ETEC and F4 or F18 loaded in TEMS. Mice that were orally administered with F4 or F18 loaded TEMS showed higher antigen-specific IgG antibody responses in serum and antigen-specific IgA in saliva and feces than mice that were immunized with antigens only.

Generation of transgenic corn-derived Actinobacillus pleuropneumoniae ApxIIA fused with the cholera toxin B subunit as a vaccine candidate.

Corn, one of the most important forage crops worldwide, has proven to be a useful expression vehicle due to the availability of established transformation procedures for this well-studied plant. The exotoxin Apx, a major virulence factor, is recognized as a common antigen of Actinobacillus (A.) pleuropneumoniae, the causative agent of porcine pleuropneumonia.

An immunosorbent assay based on the recombinant ApxIa, ApxIIa, and ApxIIIa toxins of Actinobacillus pleuropneumoniae and its application to field sera.

Actinobacillus pleuropneumoniae is the etiologic agent of porcine pleuropneumonia, a highly contagious pulmonary disease in pigs with major economic losses for pig producers worldwide. Whereas A. pleuropneumoniae isolates are divided into 15 serotypes, the isolates secrete 4 types of exotoxins (ApxI, ApxII, ApxIII, and ApxIV), which are known as major virulence factors.

Predicting genetic traits and epitope analysis of apxIVA in Actinobacillus pleuropneumoniae.

Actinobacillus pleuropneumoniae causes a severe hemorrhagic pneumonia in pigs. Fifteen serotypes of A. pleuropneumoniae express four different Apx toxins that belong to the pore-forming repeats-in-toxin (RTX) group of toxins.

Induction of Th1 polarized immune responses by thiolated Eudragit-coated F4 and F18 fimbriae of enterotoxigenic Escherichia coli.

Diarrhea in newborn and weaned piglets is mainly induced by enterotoxigenic Escherichia coli (ETEC) with fimbriae F4 (K88) and F18 (F107). In this study, we evaluated F4 and F18 coated with thiolated Eudragit microspheres (TEMS) as a candidate for an oral vaccine. The average particle sizes of TEMS, F4-loaded TEMS, and F18-loaded TEMS were measured as 4.

Comparative study of gamma interferon production in mice immunized with outer membrane proteins and whole bacteria of Brucella abortus.

Brucella abortus is the intracellular bacterium that causes bovine brucellosis and a chronic human disease known as undulant fever. Interferon (IFN)-gamma plays critical roles in defending against intracellular bacterial infection. In this experiment, we demonstrated the difference in IFN-gamma production between the splenocytes of mice inoculated with outer membrane proteins (OMPs) of B.

Renormalized resonance quartets in dispersive wave turbulence.

Using the (1+1)D Majda-McLaughlin-Tabak model as an example, we present an extension of the wave turbulence (WT) theory to systems with strong nonlinearities. We demonstrate that nonlinear wave interactions renormalize the dynamics, leading to (i) a possible destruction of scaling structures in the bare wave systems and a drastic deformation of the resonant manifold even at weak nonlinearities, and (ii) creation of nonlinear resonance quartets in wave systems for which there would be no resonances as predicted by the linear dispersion relation. Finally, we derive an effective WT kinetic equation and show that our prediction of the renormalized Rayleigh-Jeans distribution is in excellent agreement with the simulation of the full wave system in equilibrium.

Analysis of the helicase gene of Korean swine hepatitis E virus isolates and trends in viral infection.

Hepatitis E virus (HEV) has been considered to be a zoonotic agent and an important public concern worldwide. In this study, a nested RT-PCR was developed to detect the helicase gene of swine HEV (sHEV) from sera of pigs. Using this RT-PCR, 16 out of 821 Korean isolates of sHEV were identified, with 1.

Catechins inhibit angiotensin II-induced vascular smooth muscle cell proliferation via mitogen-activated protein kinase pathway.

Catechins, components of green tea, reduce the incidence of cardiovascular diseases such as atherosclerosis. Angiotensin II (Ang II) is highly implicated in the proliferation of vascular smooth muscle cells (VSMC), resulting in atherosclerosis. The acting mechanisms of the catechins remain to be defined in the proliferation of VSMC induced by Ang II.

DA-9601, a standardized extract of Artemisia asiatica, blocks TNF-alpha-induced IL-8 and CCL20 production by inhibiting p38 kinase and NF-kappaB pathways in human gastric epithelial cells.

Aim: To investigate whether, or how, DA-9601, which is a new gastroprotective agent, inhibits TNF-alpha-induced inflammatory signals in gastric epithelial AGS cells.

Methods: Cell viability was determined by MTT assay. IL-8 and CCL20 promoter activities were determined by a luciferase reporter gene assay.